Groundwater monitoring environmental objectives

According to the US Environmental Protection Agency (US EPA 1999), NA can only be relied on within the context of a carefully controlled and monitored site clean-up approach to achieve site-specific remedial objectives within a time frame that is reasonable compared to that offered by other more active methods. The natural attenuation processes that are at work in such a remediation approach include a variety of physical, chemical, or biological processes that, under favorable conditions, act without human intervention to reduce mass, toxicity, mobility, volume, or concentration of contaminants in soU and groundwater. 

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